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Updated: Feb 1, 2026
07:44
Assessment of Cerebral Lateralization in Children using Functional Transcranial Doppler Ultrasound fTCD
Published on: September 27, 2010
20.8K
Microembolic signal detection by transcranial Doppler: Old method with a new indication
Sombat Muengtaweepongsa1, Charturong Tantibundhit2
1Department of Internal Medicine, Faculty of Medicine, Thammasat University, Pathum Thani 12120, Thailand. musombat@staff.tu.ac.th.
World Journal of Methodology
|December 7, 2018
Summary
Transcranial Doppler (TCD) can detect embolic signals in stroke patients, but artefacts complicate interpretation. Automated detection methods are crucial for accurately identifying embolic signals in cryptogenic stroke patients with patent foramen ovale (PFO).
Area of Science:
- Neurology
- Cardiology
- Medical Imaging
Background:
- Transcranial Doppler (TCD) is vital for assessing intracranial blood flow and detecting embolic signals.
- Artefacts in TCD can mimic embolic signals, hindering accurate diagnosis, especially in stroke patients.
- Patent foramen ovale (PFO) is linked to cryptogenic stroke, prompting renewed interest in PFO closure for secondary prevention.
Discussion:
- Distinguishing true embolic signals from artefacts in TCD requires expert interpretation, impacting TCD's utility.
- The agitated saline contrast method with TCD can confirm emboli passage through PFO to the brain.
- Automated embolic signal detection can enhance TCD's role in evaluating cryptogenic stroke patients with PFO.
Key Insights:
- TCD's effectiveness in detecting embolic signals is challenged by artefacts.
- Recent trials highlight PFO closure's benefit in recurrent stroke prevention, increasing PFO relevance.
- TCD with agitated saline bubbles is a key method for detecting paradoxical emboli in PFO-associated stroke.
Outlook:
- Developing automated TCD analysis can improve diagnostic accuracy for embolic signals.
- Further research on PFO closure efficacy in cryptogenic stroke is warranted.
- Integrating advanced TCD techniques may optimize stroke management and prevention strategies.
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